The present invention relates to a novel earth moving device. More particularly, the invention is directed to an earth moving device which can be attached to the front end of an endless track vehicle and which can be used for moving earth, and obstacles on and within the earth, to the side of the vehicle.
In today's military environment, it is often necessary to quickly establish a path suitable for travel by people or vehicles. In establishing such a path, it will often be necessary to remove both landmines and surface obstacles such as concrete or Jersey barriers. A number of different machines have been designed to address this objective. All of these machines have failed to fully satisfy the above objectives.
One particular device which has been developed is a mine-clearing rake. The mine clearing rake is mounted on the front of a tank or other endless track vehicle. The rake engages the ground in front of the tank and pushes the ground, including any mines within the ground, to the front of the tank, thus leaving a path behind the tank.
Another device for clearing such a path also involves attaching a device to the front of a tank. This second device is a V-shaped blade with the center of the V in the center of the vehicle. The V-shaped blade also has ground engaging teeth on its lower end. The device is thus used to engage the ground and to push the earth in front of the vehicle to either side of the vehicle.
A major disadvantage with each of these devices is that the earth can accumulate in front of the device and thus will not properly be pushed to the side of the vehicle. As material accumulates in front of the device, a larger and larger propelling force is required to sustain forward movement of the vehicle. Therefore, because the earth tends to accumulate in front of the vehicle, larger propelling vehicles are required. The use of larger propelling vehicles is both more expensive and less efficient. Further, while the above devices are used to clear a path where landmines are found within the earth, these two devices are not well suited for clearing a path when larger obstacles are disposed upon the earth, such as concrete barriers.
Yet another device that has been proposed for clearing such a path is the device disclosed in U.S. Pat. No. 4,358,905. This device is mounted on the front end of an endless track vehicle. The device has a lower blade which engages the earth. The earth then encounters a laterally disposed rotating track that moves the earth to the side of the track. This device does not have the disadvantage of earth accumulating in front of the vehicle because the track continuously moves the earth to the side of the vehicle. However, this device also has several disadvantages. First, the ends of the rotating track are exposed. When the ends of the track are exposed, the track can be more easily damaged. This is especially true when concrete barriers are encountered. Further, when the ends of the track are exposed the likelihood that foreign matter will become wedged between the track and the support frame increases, thus decreasing the reliability of the device. Second, the lower blade on the bottom of the device is not well suited for severing a layer of earth beneath the level containing any landmines. Third, when this device is used, the propelling vehicle tends to stray from a straight path. Thus, when this device is used, the operator of the vehicle must constantly monitor and correct the path of the vehicle to attempt to form a straight path.
Therefore, a device is needed which will clear a path within the earth. Further, a device is needed which will clear such a path when the earth contains landmines and when obstacles, such as concrete barriers, are disposed on top of the earth.
A device is also needed that will clear a path within the earth by continuously and positively moving the earth to the side of the vehicle, thus allowing the propelling vehicle to operate without the engaged earth accumulating in front of the vehicle.
Still further, a device is needed that will clear a path within the earth and that will encourage the propelling vehicle to travel in a straight path.